Knitted fabric pick testing device



July 17, 19 R. B. THOMAS ETAL KNITTED FABRI C PICK TESTING DEVICE Filed Jan. 7, 1960 2 Sheets-Sheet 1 1N VENTORS ATTORNEYS.

y 1962 R. B. THOMAS ET AL 3,044,293

KNITTED FABRIC PICK TESTING DEVICE Filed Jan. 7, 1960 2 Sheets-Sheet 2 FICF': B-

o o o 9000,99; oooooooooo a cg ocooooooo INVENTORS. Emmy 19. 720M961.

ATTORNEYS.

United States Patent 3 044,293 KNITTED FABRIC PICK TESTING DEVICE Ronny B. Thomas and Harvey N. Young, Winston-Salem,

N.C., assignors to Hanes Hosiery Mills Company,

/ This invention relates to a device for determining the pick propensity of knitted fabrics, particularly of womens stockings. I

In the textile industry, and especially in the knitting of ladies hosiery, it is deemed important that the hosiery be highly resistant to picks or to picking. In the language of the industry, a pick is a loop or stitch which has been pulled out of its normal alignment relative to adjacent loops or stitches as a result of having engaged with an extraneous protrusion, such as a sharp point or a rough surface, or even as a result of having engaged with another loop of the same fabric. The presence of picks in ladies nylon hosiery, usually knitted of fine denier yarn, is considered an unsightly imperfection and causes the stocking to be downgraded in price or in the alternative requires the removal of such picks by additional manufacturing steps and procedures at consequent additional cost.

It has been observed that some stockings are more prone to picking than others and that such proneness to picking may be due either to the construction of the fabric or to certain inherent characteristics in the yarn itself.

A definite demand has existed for some time for a device and test procedure which will determine the relative propensity of hosiery and other knitted fabrics to picking. The present invention provides such a device and such a method.

Our invention will be understood clearly from a consideration of the following detailed description of a preferred embodiment illustrated in the drawing in which:

FIG. 1 is a side elevational view, partly broken away, of a device embodying our present invention;

FIG. 2 is an end elevational view, partly broken away, of the device of FIG. 1;

FIG. 3 is a detailed view, in cross section of a straight pin insert as seen along the line III--III of FIG. 1;

FIG. 4 is a detailed view in cross section of a bent pin insert as seen along the line IVIV of FIG. '1;

FIG. 5 is an illustration of a cork insert carrying a straight pin;

FIG. 6 is an illustration of a cork insert carrying a hooked pin; and

FIG. 7 is a view, in cross section, along the line VII-- VII of FIG. 2 showing a bailie plate secured to the drum.

In describing the preferred embodiment of our invention illustrated in the drawing, specific terminology has been resorted to for the sake of clarity. However, it is not our intention to be limited to the specific terms so selected, and it is to be understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose.

Referring now to FIGS. 1 and 2, the device of our invention, in preferred form, comprises a cylindrical drum 10 mounted for motor-driven rotation about a horizontal axis. The means for mounting the drum may take any suitable and convenient form. In the drawing we have shown drum 10 supported between a of pipe standards 12 and '13 mounted on a plywood base plate 14. The drum is driven rotationally at relatively low speed (17 r.p.m. in the preferred embodiment) by a low speed electric motor adapted to be turned on and off by a switch 16. The means coupling motor 15 to the drum 10 may take any suitable and convenient form. In the "ice drawing we have shown motor 15 driving V-belt 2 0 through suitable reduction gearing =17, shaft 18 and pulley 19. The V-belt 20 drives a pulley 22 fixed to a horizontally positioned shaft 24 mounted on the right side wall 26 of the drum 10 as by a plate 29. Shaft 24 is journaled for rotation in a collared bearing 30 in support standard 13.

On the left side of drum 10 (as viewed in FIG. 2) a corresponding horizontal shaft 3 2 is mounted by plate 33 on the left side wall 34 of the drum and is journaled for rotation in collared bearing 36 in support standard 12.

In accordance with our invention, the circumferential wall 40 of the cylindrical drum 10 is a perforated metal sheet having a large number of circular holes for receiving a plurality of pin-carrying tapered plugs inserted at selected or random locations.

Preferred forms of plugs are shown in FIGS. 5 and 6. In FIG. 5, the plug 50 is an 000 cork having a blued straight pin 52 inserted through the axis of the. cork with the pointed end 53 protruding from the larger diameter end 5-5 of the cork.

In FIG. 6, plug 50 is shown as having inserted through its axis a blued pin 54 Whose protruding pointed end 56 is bent at an angle from 30 to 60, preferable 45, with respect to the shank of the pin.

In accordance with our invention, frusto-conical plugs of suitable material, preferably cork, having sharp points protruding from the larger diameter ends thereof are inserted selectively or at random through a number of holes in the perforated circumferentialwall 40* of drum 10. The plugs are inserted through the holes from the inside of the drum, the smaller diameter end of the plug entering the hole first. The plugs take up the position shown in cross section FIGS. 3 and 4 with the larger diameter end being substantially flush with the inside surface of the perforated circumferential Wall 40.

Also in accordance with our invention, baflie bars 60, 61, 62 and 63 are mounted across the drum adjacent the inside surface of the perforated circumferential wall 40 and at widely spaced preferably regular intervals. In the illustrated embodiment, four bafiie bars 60, 61, 62 and 63 are shown spaced apart, as clearly seen in FIG. 1. If desired, a somewhat larger number of halide bars may be employed. One manner in which the baffle bars may be mounted is shown in cross section in FIG. 7. As there shown, baffle bar 60 is held by a cross rod 57 extending between the side walls 34, 26 of the drum and held in place as by nuts 58, as clearly seen in FIG. 2. A

centrally positioned bolt 59* holds the baflie bar against radial displacement.

The side walls 26, 34 of the drum 10* are preferably solid, for example, plywood. One of the side walls, 34 in the illustration, is provided with an access door 7 0 normally held in closed position as by spring-loaded hinges 72, 74 and a stop 75. When loading or unloading the drum, access door 70 may be conveniently held open as by a hook chain 76 which when not in use may be hooked to standard 12 as by an eye bolt 77.

In operation, the drum 10 is driven rotationally at a relatively low speed to tumble the stocking or other fabric 78 about in random manner, the bafiie bars 60-63 assisting in effecting agitation and random tumbling of the fabric.

Prior to placing the stocking (or other fabric to be tested) inside the drum, the number of picks are carefully counted. This may be done most effectively by visual inspection of the stocking while pulled on a conventional black hosiery inspection board and marking the picks with a colored crayon. The stocking (or other fabric) is then placed into the drum, the motor is started and the drum is rotated for a definite time interval, as measured by timer 80, after which the stocking is removed and the number of picks again counted, using the same procedure as above described. The difference in the pick count before and after the test run is then compared with a similar pick count run on a standard or control stocking. We have found that such comparison is a direct measure of the pick propensity of the particular stocking fabric being tested. For increased reliability of the test, each stocking is tested inside-out as well as right-side out to obtain an average pick count. We also prefer to test a numher of stockings of the same fabric or knit to obtain a rating for comparison with a standard.

We have found that the. device illustrated provides a simple but highly useful device for testing the pick propensity of knitted fabrics, particularly womens knitted nylon hosiery. I

The particular device illustrated has the following specifications but it will be understood of course, that various modifications may be made without departing from our invention as claimed: 1

The drum has a diameter of 2 feet and a width of 6 inches. It is supported by two 1" iron pipe standards on a 2 x 1V2 base of plywood. The sides of the drum are plywood; the circumferential wall is perforated sheet metal. The drum is driven by a motor having a speed of 57 rpm. which is reduced by reduction gearing to 17 r.p.m. at the driving shaft. The plugs are 000 cork. The pins are blued pins, straight and hooked at 45. A belt drive is shown and described but a gear drive could just as readily be used. In that case, the support stand would be modified to accommodate the gear drive.

Such modifications, and others, are of course, well within the concept of our invention.

Having thus described our invention, we claim: 1. A device for determining the propensity to picking of womens knitted hosiery, said device comprising; a cylindrical drum for containing a fabric to be tested, said drum having solid side walls and a perforated circumferential wall; a plurality of bafiie bars mounted at regular intervals adjacent the inside surface of said circumferential wall for causing random movement of said fabric during rotation of said drum; a plurality-of frusto-conical plugs inserted from inside said drum through selected holes of said perforated circumferential walls at spaced-apart irregular locations, the inner end surface of said plugs being substantially flush with the inside surface of said circumferential wall; pins protruding from the inner end surface of said plugs; means mounting said drum for rotation about its axis in horizontal position; and means for driving said drum rotationally about its axis to tumble the fabric contents of said drum against said pins.

2. A device as claimed in claim 1 characterized in that the protruding shank of at least some of said pins is bent at an angle of between 30 and 60.

3. A device as claimed in claim 2 characterized in that said plugs are cork.

4. A device as claimed in claim 2 characterized in that the protruding shank of at least some of said pins is bent at an angle of 

